The wchar_t keyword designates a wide-character type. The wchar_t type is defined by MIDL as an unsigned short (16-bit) data object.
The MIDL compiler allows redefinition of wchar_t, but only if it is consistent with the preceding definition.
The wide-character type is one of the predefined types of MIDL. The wide-character type can appear as a type specifier in const declarations, typedef declarations, general declarations, and function declarators (as a function-return-type specifier and as a parameter-type specifier). For the context in which type specifiers appear, see IDL.
The string attribute can be applied to a pointer or array of type wchar_t.
Use the L character before a character or a string constant to designate the wide-character-type constant.